CDP

ESP32/CDP/LLDP/DHCP – Third Edition

This is the third major update to the CDP/LLDP packet sniffer (First, Second). The main processor is now the ESP32 microprocessor. Of the available packages, I’ve chosen the TTGO T-Display. I would like to give a shout-out to Colin for his assistance, and for testing what has been (at times) some cringe worthy code. There has been some pretty poor work-arounds to resolve issues, and then (hopefully) cleaned them up later. If you notice any remaining please let me know. You can see below that the wiring is far simpler than the previous versions. This is thanks to the T-Displays extra built in options. The major changes in the T-Display: built in TFT, charging circuit, and Bluetooth. The red mosfet is used to distribute power to peripheral devices. The reason for the mosfet is to… Read More »ESP32/CDP/LLDP/DHCP – Third Edition

Arduino CDP Revisited

UPDATE 5/5/21: Please check out the most current version. During some down time I’ve decided to revisit the Arduino CDP sniffer and add extra features. This will be a running post and will be updated periodically. As mentioned in the comments of the other post I will be looking at adding LLDP support and an export feature to a mobile/laptop. The export or “history” addition will allow a log to be saved to an external device as easy as possible. As a prototype, it’s had an ESP8266 added to it with a web server running showing modified serial output. Initial results work, but I’m again getting plagued with power issues from the ESP8266’s. Getting those 3.3v and enough amps into the original container will be problematic. The benefit of this is it’s exported as text… Read More »Arduino CDP Revisited

CDP Sniffing with an Arduino

UPDATE 5/5/21: Please check out the most current version. Firstly full credit to Chris van Marle for his work on his CDPSniffino code, of which I have butchered (to be honest) to get it to work with ENC28J60 ethernet controllers. The packet info that is captured is slightly different, so it took a while debugging. This is also my first Arduino project (not including 3D printers). It has been a while since I have written C code… Enough excuses… Anyway, I use a lot of Cisco equipment and I have found on many occasion that network wall ports are either not labeled or the labels have worn off. When that port needs to be reconfigured it can take time to work out which network cabinet it goes back too, then which switch, and then which… Read More »CDP Sniffing with an Arduino